Legal-Tradition
The UCC operates under the law merchant, not the common law
Examining the movement claim that modern commercial law — the UCC, descended from the law merchant — is the controlling primary law for commercial transactions, with common-law contract relegated to a subordinate supplement. Properly disambiguated and cabined to the Code's scope, the claim holds: the UCC's own text makes it primary, and the rules of its commercial core are law-merchant-derived, not common-law-contract-derived. The overreach is the leap from there to 'all law is commercial.'
Imprisonment for debt was a merchant-law innovation, unknown to the early common law
Examining the claim that imprisonment for debt was a law-merchant innovation, unknown to the common law — and that the Supreme Court in Sturges v. Crowninshield said so. The narrow truth holds: it was alien to the English common law, which imported it by statute in the 1280s. But it was no innovation — debt bondage is ancient and near-universal (Scripture, Rome) — the Sturges line is counsel's argument rather than the Court's, and the inference that modern incarceration is therefore commercial does not follow.
Law Merchant (Lex Mercatoria)
The body of customary commercial law that grew out of medieval European trading fairs, was administered by merchant courts, and was absorbed into the common law and later codified — surviving in the modern Uniform Commercial Code, which names it by its own terms as a supplementary source. A real and recognized legal tradition; the question Adverse Review presses is how much of the modern commercial system it actually governs.
Common Law
One of the most overloaded terms in legal argument: it names at least seven distinct things — judge-made law as opposed to statute; the 'law' side of the law/equity divide; the Anglo-American tradition as opposed to civil, merchant, or admiralty law; the specific historical body of English doctrine; a customary or natural-law ideal; the now-abolished general federal common law; and the entire accumulated body of judicial precedent. Most confusion in the alternate-law community — and more than one error on this site — comes from sliding between these senses inside a single argument.